Reduction gear comprising central shaft and transmission element superimposed and centered by said shaft

Abstract

The invention relates to a reduction gear (3) for a geared motor (1), comprising a central shaft (50) for centering a first transmission element (4) and a second transmission element (7). The first transmission element (4) is spaced apart from the second transmission element (7) in the longitudinal direction (X3-X3) of the central axis and is rotatably movable relative to the second transmission element (7). At least one of the first transmission element (4) and the second transmission element (7) comprises coaxial cogwheel (42) and pinion (44) which are superposed in the longitudinal direction (X3-X3) of the central axis and are rotationally connected to each other.

Description

Technical Field

[0001] The present invention relates to a gear motor, and more particularly to a gear motor for a cooling system of a motor vehicle. Background Art

[0002] Gear motors for motor vehicles typically consist of an electric motor and a planetary reduction gear. While these planetary reduction gears typically offer satisfactory reduction ratios, they are relatively large along their longitudinal axis, which is the height of the reduction gear. Consequently, positioning the electric motor and gear motor within the vehicle is often difficult.

[0003] There are also reduction gears that include stepped gears, each of which includes a coaxial gear and a pinion. The reduction ratio of these reduction gears is satisfactory, but they have a large transverse dimension.

[0004] There is a need to reduce the size of the reduction gear of a gearmotor while aiming to increase the reduction ratio of the reduction gear and to limit the gearmotor mass. Summary of the Invention

[0005] In this respect, the present invention relates to a reduction gear for a gear motor. The reduction gear comprises a first tangentially meshing motion transmission element and a second tangentially meshing motion transmission element. The reduction gear further comprises a central shaft for centering the first transmission element and the second transmission element.

[0006] The first transmission element is spaced apart from the second transmission element along the longitudinal direction of the central axis. The first transmission element is rotatably movable relative to the second transmission element.

[0007] At least one of the first transmission element and the second transmission element includes a coaxial cogwheel and pinion gear, which are superimposed along the longitudinal direction of the central axis and are rotationally connected to each other.

[0008] Thanks to the reduction gear according to the invention, the reduction gear is more compact and has a relatively low mass and a high reduction ratio.

[0009] In particular, the reduction gear according to the present invention is more compact than a multi-stage reduction gear of known structure, while aiming to increase the reduction ratio of the reduction gear under equivalent reduction gear mass.

[0010] The reduction gear according to the invention is more compact in the height direction of the reduction gear than planetary reduction gears of known construction, while aiming at increasing the reduction ratio at an equivalent reduction gear mass.

[0011] The present invention may selectively include one or more of the following features, which may or may not be combined with each other.

[0012] According to a specific embodiment, the reduction gear comprises a third stage gear mechanically meshing with the first transmission element and the second transmission element. The third stage gear comprises a coaxial cogwheel and a pinion, which are superimposed along the longitudinal direction of the intermediate shaft and are rotationally connected to each other.

[0013] According to a particular embodiment, the central shaft is the output shaft of the reduction gear.The second transmission element is the output gear of the reduction gear.

[0014] According to one embodiment, the output gear comprises a cogwheel and a first mechanical coupling portion, the first mechanical coupling portion being configured to mesh with a second mechanical coupling portion mechanically connected to the output gear by form fit.

[0015] According to a particular embodiment, the reduction gear comprises a stepped gear train with tangential gears. The stepped gears each comprise a coaxial cogwheel and a pinion, the cogwheel and the pinion being superimposed and rotationally connected to one another. The stepped gears are arranged around axes that are parallel to one another.

[0016] According to a particular embodiment, the gear set of the reduction gear is composed of a stepped gear train and an output gear. The pinion of each stepped gear is mechanically meshed with a cogwheel of a stepped gear of the stepped gear train or a cogwheel of the output gear.

[0017] The present invention also relates to a bracket for supporting and centering at least one reduction gear shaft of a geared motor. The reduction gear shaft is a shaft for centering at least one first motion transmission element and a second motion transmission element. The first and second transmission elements are spaced apart from each other in the longitudinal direction of the shaft and are rotatably movable relative to each other.

[0018] The bracket includes at least one first plate for supporting the second transmission element and / or the first transmission element. The first plate is configured to be passed through by the shaft and is located between the first transmission element and the second transmission element.

[0019] Thanks to the bracket according to the present invention, the mechanical strength of the reduction gear and the reduction ratio of the reduction gear are improved. In particular, the bracket limits the bending of the central shaft and the wear of the first transmission element, the second transmission element and the central shaft.

[0020] The bracket particularly improves the centering of the first transmission element and the second transmission element, while limiting vibrations of the reduction gear and mechanical forces exerted on the central shaft, the first transmission element and the second transmission element. The bracket, for example, facilitates the transmission of mechanical forces between the reduction gear and the reduction gear housing.

[0021] The present invention also relates to a gear reduction device, comprising the reduction gear and the bracket described above. The reduction gear shaft is a central shaft. The central shaft passes through the first plate, and the first plate is axially located between the first transmission element and the second transmission element.

[0022] According to a particular embodiment, the support comprises a second plate laterally spaced apart from the first plate.The second plate is a support for the third stage gear.

[0023] Finally, the present invention relates to a gear motor comprising a gear reduction device as described above, an electric motor and a housing.

[0024] According to a particular embodiment, the support comprises a base carrying the first plate, the base resting on a side wall of the housing. The support comprises a support foot resting on the bottom of the housing. The foot supports the first plate relative to the housing.

[0025] According to a particular embodiment, the legs of the support are each traversed by a connecting rod in order to connect the support to the housing.

[0026] Preferably, the bracket comprises at least three legs. Preferably, the connecting rod is a connecting screw.

[0027] According to a particular embodiment, the gear motor comprises a cover, the central shaft being rigidly connected to the cover. Preferably, the central shaft is in mechanical engagement with the cover.

[0028] According to a particular embodiment, the shaft for centering the third stage gear is rigidly connected to the support, in particular to the second plate.

[0029] According to a particular embodiment, the axis of the step gear is parallel to the axis of the electric motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The present invention will be better understood by reading the description of the exemplary embodiments and referring to the accompanying drawings, in which:

[0031] Figure 1 is a schematic perspective view of a gear motor according to a first embodiment of the present invention;

[0032] Figure 2 is a schematic cross-sectional view of a gear motor according to a first embodiment;

[0033] Figure 3 is a schematic longitudinal sectional view of a gear motor according to a first embodiment;

[0034] Figure 4 is a schematic diagram of a gear motor according to a first embodiment, wherein the reduction gear is an exploded view;

[0035] Figure 5 is a schematic bottom perspective view of a bracket for supporting and centering a gear motor shaft according to a first embodiment;

[0036] Figure 6 is a schematic top perspective view of a bracket of the gear motor according to the first embodiment. DETAILED DESCRIPTION

[0037] Identical, similar or equivalent parts in different figures are provided with the same reference numerals in order to facilitate transition from one figure to another.

[0038] Figure 1 A geared motor 1 is shown for a cooling system of a motor vehicle, typically a car.

[0039] refer to Figures 1 to 4 The gear motor 1 includes a housing 10, a cover 14, an electric motor 2, a control member 16, a reduction gear 3 and a bracket 8. The gear motor 1 is used to actuate a coolant pilot valve, a radiator valve, etc., for example.

[0040] The housing 10 includes a side wall 11 , a bottom 12 and an electrical connector 13 . In the embodiment shown, the side wall 11 and the bottom 12 form an integral housing wall. The housing 10 is configured to accommodate the motor 2 and the reduction gear 3 .

[0041] The bottom 12 comprises three blind holes forming a first connection and centering aperture 12a of the motor shaft 20 of the electric motor 2 , a second connection and centering aperture 12b of the input shaft 40 of the reduction gear 2 , and a third connection and centering aperture 12c of the intermediate shaft 60 .

[0042] The electrical connector 13 is configured to be connected to a vehicle control unit or a vehicle power source (eg, a vehicle battery) to supply power to the electric motor 2 .

[0043] The cover 14 includes three blind holes, which respectively form a first connection and centering hole 14a for the motor shaft 20, a second connection and centering hole 14b for the input shaft 40 of the reduction gear, and a third connection and centering hole 14c for the central shaft 50. The cover 14 is configured to tightly close the housing 10.

[0044] The motor 2 includes a motor shaft 20 and a rotor pinion 21. The motor shaft 20 and the rotor pinion 21 are arranged around a longitudinal axis X1-X1 of the motor shaft 20. The motor 2 is, for example, a brushless DC motor. The motor 2 is configured to rotate the reduction gear 3.

[0045] The motor shaft 20 is connected to the cover 14 at its upper longitudinal end, for example by fitting into the first connecting hole 14a. The motor shaft 20 of the electric motor is connected to the base 12 at its lower longitudinal end, for example by snapping into the first connecting hole 12a. The input shaft 40 is used to center the rotor pinion 21.

[0046] refer to Figure 4 The control member 16 is, for example, an electronic control card for the electric motor 2. Specifically, it includes components for controlling the power of the electric motor and means for connecting and exchanging data. The control member 16 is configured to control the power supply to the electric motor 2 according to instructions from a vehicle control unit (not shown).

[0047] Combined with reference Figures 2 to 4 The reduction gear 3 includes a first-stage gear 4, a second-stage gear 5, a third-stage gear 6, and an output gear 7. In the embodiment shown, the gear set of the reduction gear 3 consists of the stepped gear train 4, 5, 6, and the output gear 7. The reduction gear 3 also includes an input shaft 40, a center shaft 50, and an intermediate shaft 60, around which the stepped gears 4, 5, 6, and the output gear 7 are arranged.

[0048] The reduction gear 3 is configured to reduce the speed of the output end of the reduction gear 3 (relative to the speed of the output end of the motor 2) and increase the torque of the output end of the reduction gear 3 (relative to the torque of the output end of the motor 2). The reduction gear 3 and the bracket 8 together form a gear reduction device of the gear motor.

[0049] Each of the step gears 4, 5, 6 and the output gear 7 is a tangentially meshing motion transmission element. These transmission elements are rotatably movable relative to each other.

[0050] Each stepping gear 4, 5, 6 includes a cogwheel 42, 52, 62 and a pinion 44, 54, 64 that are coaxial, superimposed, and rotationally connected to each other. More specifically, in the illustrated embodiment, each stepping gear 4, 5, 6 is integral. The pinion 44, 54, 64 of each stepping gear 4, 5, 6 is mechanically meshed with a cogwheel 52, 62 or an output gear 72 of a stepping gear of the stepping gear train.

[0051] The first-stage gear 4 includes a coaxial first cogwheel 42 and a first pinion 44, which are stacked along the longitudinal direction X2-X2 of the reduction gear input shaft 40. The first-stage gear 4 is driven to rotate by the motor 2, and the first-stage gear 4 drives the second-stage gear 5 to rotate. The first cogwheel 42 is mechanically meshed with the rotating rotor pinion 21. The first pinion 44 is mechanically meshed with the second cogwheel 52, causing it to rotate.

[0052] The second-stage gear 5 includes a second cogwheel 52 and a second pinion 54, which are coaxial and superimposed along the longitudinal direction X3-X3 of the central axis. The second-stage gear 5 is driven to rotate by the first-stage gear 4, and the second-stage gear 5 drives the third-stage gear 6 to rotate. The second pinion 44 mechanically meshes with the third cogwheel 62 and causes it to rotate.

[0053] The third-stage gear 6 includes a third cogwheel 62 and a third pinion 64, which are coaxial and superimposed along the longitudinal direction X4-X4 of the intermediate shaft 60. The third-stage gear 6 is driven to rotate by the second-stage gear 5, and the third-stage gear 6 drives the output gear 7 to rotate. The third pinion 64 mechanically meshes with the output cogwheel 72 of the reduction gear and causes it to rotate.

[0054] The output gear 7 includes an output cogwheel 72 and a first mechanical coupling portion 74. The cogwheel 72 and the first mechanical coupling portion 74 are coaxial about the central axis 50 and are rigidly connected in rotation. In the illustrated embodiment, the output gear 7 is integral. In the illustrated embodiment, the first mechanical coupling portion 74 is configured to mesh with the second mechanical coupling portion mechanically connected to the reduction gear 3 through a form fit, particularly through a complementary form. The output gear 7 is the output gear of the reduction gear 3.

[0055] The shafts 40, 50, 60 of the grading gears are parallel in pairs. The shafts 40, 50, 60 of the grading gears are also parallel to the motor shaft 20.

[0056] The input shaft 40 is connected to the cover 14 at its upper longitudinal end, for example, by snapping into the second connecting hole 14b. The input shaft 40 is connected to the base 12 at its lower longitudinal end, for example, by snapping into the second connecting hole 12b. The input shaft 40 is used to center the first-stage gear 4.

[0057] The central shaft 50 is connected to the cover 14 at its upper longitudinal end, for example by snapping into the third connecting hole 14c. The central shaft 50 is mechanically engaged with the output gear 7 at its lower longitudinal end, for example by idling assembly, while being rotatably movable relative to the output gear 7.

[0058] The central shaft 50 is used to center the second stage gear 5 and the output gear 7. The central shaft 50 is also the output shaft of the reduction gear, and the output gear 7 is spaced apart from the second stage gear 5 along the longitudinal axis X3-X3 of the central shaft.

[0059] The intermediate shaft 60 is connected at its upper longitudinal end to the bracket 8, for example by snapping into the central hole 86a of the second plate 86. The intermediate shaft 60 is connected at its lower longitudinal end to the base 12, for example by snapping into the third connecting hole 12c. The intermediate shaft 60 is used to center the third stage gear 6.

[0060] Combined with reference Figures 2 to 6 The bracket 8 includes a base 80, legs 82, a first plate 84, a second plate 86, and a retaining portion 83. The bracket 8 is a bracket for supporting and centering the central shaft 50. It is used to transmit mechanical forces to the housing 10, especially those forces that tend to bend the central shaft 50, and to limit vibration of the reduction gear 3.

[0061] In the illustrated embodiment, the bracket 8 includes three legs 82. The legs 82 are preferably spaced equidistant from each other. Each leg 82 extends from the base 80 to the bottom 12 of the housing. A connecting rod, typically a threaded screw, passes through each leg 82 to connect the bracket 8 to the housing 10. The legs 82 support the base 80 relative to the bottom 12 of the housing 10.

[0062] The base 80 carries a first plate 84. The base 80 includes a second plate 84. The base 80 is used to support and center the second stage gear 5 and the third stage gear 6. The upper and lower surfaces of the base are substantially planar and perpendicular to the longitudinal axis X3-X3 of the central shaft 50.

[0063] First plate 84 is pierced by a central aperture 84a through which central shaft 50 extends. First plate 84 is axially positioned between second-stage gear 5 and output gear 7 relative to central shaft 50. First plate 84 has an upper surface and a substantially planar inner surface that are substantially parallel to base 80 and perpendicular to the longitudinal axis X3-X3 of the central shaft. First plate 84 serves as a support plate for output gear 7 and / or second-stage gear 5, particularly for pinion 54 of second-stage gear 5.

[0064] The first plate 84 is connected to the base by at least one connecting portion 83, and in the embodiment shown there are three connecting portions. Each connecting portion 83 extends about the central axis 50, substantially perpendicular to the base 80 and the first plate 82 to which it is mechanically connected.

[0065] The second plate 86 extends substantially parallel to the second cogwheel 52 and the third cogwheel 62. The second plate 86 is located on the lower surface of the base 80. With respect to the central axis 50, it is axially located between the second-stage gear 5 and the third-stage gear 6. The second plate 86 includes a central aperture 86a through which the intermediate shaft 60 is inserted to connect the intermediate shaft 60 to the bracket 8. The second plate 86 serves as a support member for the third-stage gear 6.

[0066] In the embodiment shown, the middle aperture 86 a is a blind hole. The second plate 86 has a truncated circular outer profile such that the third cogwheel 62 projects laterally from the second plate 86 .

[0067] Thanks to the present invention, the reduction gear 3 is more compact while having a relatively low mass and a high reduction ratio.

[0068] In particular, the reduction gear 3 is more compact than a multi-stage reduction gear of a known structure, while aiming to increase the reduction ratio of the reduction gear 3 under an equivalent reduction gear mass. The reduction gear 3 is more compact than a planetary reduction gear in the height direction of the reduction gear 3, while aiming to increase the reduction ratio under an equivalent mass of these reduction gears.

[0069] The mechanical strength of the reduction gear 3 and the reduction ratio of the reduction gear 3 are improved thanks to the bracket 8. In particular, the bracket 8 limits the bending of the central shaft 50 and / or the wear of the second-stage gear 5, the output gear 7 and the central shaft 50.

[0070] The bracket 8 improves the centering of the second-stage gear 5 and the output gear 7, while limiting the vibration of the reduction gear 3 and the mechanical forces applied to the central shaft 50, the second-stage gear 5 and / or the output gear 7. The bracket 8 promotes the transmission of mechanical forces between the reduction gear 3 and the reduction gear housing 10.

[0071] Of course, those skilled in the art can make various modifications to the invention just described without departing from the scope of the present disclosure.

[0072] Alternatively, the bottom 12 of the housing is connected to the side wall 11 of the housing 10 .

[0073] Alternatively, the electric motor 2 is, for example, a brushed motor. The electric motor 2 is, for example, single-phase or three-phase.

[0074] Alternatively, the reduction gear 3 includes at least one non-stepped gear, such as two cogwheels, in addition to the output gear 7 .

[0075] Alternatively, the pinion 44, 54, 64 of at least one step gear 4, 5, 6 is connected to the corresponding cogwheel 42, 52, 62. Alternatively or in addition, the first coupling part 74 is connected to the output cogwheel 72.

[0076] Alternatively, the bracket 8 comprises two legs 82 or the bracket comprises four or more legs 82. Alternatively, the legs 82 are not connected to the housing 10, but the bracket 8 only rests laterally on the housing 10, in particular on the bottom 12 of the housing.

[0077] Alternatively, the support 8 rests against the side wall 11 of the housing, for example at the base 80 .

[0078] Additionally or alternatively, the bracket 8 is connected to the cover 14. In this case, the bracket 8 is configured to transfer mechanical forces from the second stage gear 5, the output gear 7 and / or the central shaft 50 to the cover 14, for example to the housing 10.

[0079] Alternatively, the bracket 8 includes a single retaining portion 83 that extends circumferentially around the central axis 50 , at least over a majority of the circumferential length around the central axis 50 .

[0080] Alternatively, the second plate 86 has, for example, a circular outer contour, such that it covers the third cogwheel 62 substantially completely.

[0081] Alternatively or in addition, the intermediate aperture 86 is a through hole. In this case, the intermediate shaft 60 is connected to the cover 14, for example at its upper end.

Claims

1. A reduction gear (3) for a gear motor (1), comprising: a first tangential meshing motion transmission element (5), a second tangential meshing motion transmission element (7), and a central axis (50) for centering the first transmission element (5) and the second transmission element (7), The first transmission element (5) is spaced apart from the second transmission element (7) along the longitudinal direction (X3-X3) of the central axis, and the first transmission element (5) is rotatably movable relative to the second transmission element (7). At least one of the first transmission element (5) and the second transmission element (7) comprises a coaxial cogwheel (52) and a pinion (54) superimposed along the longitudinal direction (X3-X3) of the central axis and connected in rotation to each other, The reduction gear (3) includes a third-stage gear (6) mechanically meshed with the first transmission element (5) and the second transmission element (7), and the third-stage gear (6) includes a coaxial cogwheel (62) and a pinion (64) superimposed along the longitudinal direction (X4-X4) of the intermediate shaft and rotationally connected to each other.

2. The reduction gear (3) according to claim 1, wherein: The central shaft (50) is the output shaft of the reduction gear, and the second transmission element (7) is the output gear of the reduction gear (3).

3. Reduction gear (3) according to the preceding claim, wherein The output gear (7) comprises a cogwheel (72) and a first mechanical coupling portion (74) configured to mesh with a second mechanical coupling portion configured to be mechanically connected to the output gear (7) through form fit.

4. A reduction gear (3) according to any one of the preceding claims, wherein The reduction gear (3) comprises a stepped gear train (4, 5, 6) with tangential gears, each of the stepped gears (4, 5, 6) comprising coaxial cogwheels (42, 52, 62) and pinions (44, 54, 64) superimposed and rotationally connected to one another, and the stepped gears (4, 5, 6) are arranged around axes (40, 50, 60) parallel to one another.

5. Reduction gear (3) according to the preceding claim, wherein The gear set of the reduction gear (3) consists of the stepped gear train (4, 5, 6) and the output gear (7), and the pinion (44, 54, 64) of each stepped gear (4, 5, 6) is mechanically engaged with the cogwheel (42, 52, 62, 72) of another stepped gear of the stepped gear train or the gear of the output gear (7).

6. A reduction gear (3) for a gear motor (1), comprising: a first tangential meshing motion transmission element (5), a second tangential meshing motion transmission element (7), and a central axis (50) for centering the first transmission element (5) and the second transmission element (7), The first transmission element (5) is spaced apart from the second transmission element (7) along the longitudinal direction (X3-X3) of the central axis, and the first transmission element (5) is rotatably movable relative to the second transmission element (7). At least one of the first transmission element (5) and the second transmission element (7) comprises a coaxial cogwheel (52) and a pinion (54) superimposed along the longitudinal direction (X3-X3) of the central axis and connected in rotation to each other, The reduction gear (3) comprises a stepped gear train (4, 5, 6) with tangential gears, each of the stepped gears (4, 5, 6) comprising coaxial cogwheels (42, 52, 62) and pinions (44, 54, 64) superimposed and rotationally connected to one another, and the stepped gears (4, 5, 6) are arranged around axes (40, 50, 60) parallel to one another.

7. Reduction gear (3) according to the preceding claim, wherein The gear set of the reduction gear (3) consists of the stepped gear train (4, 5, 6) and the output gear (7), and the pinion (44, 54, 64) of each stepped gear (4, 5, 6) is mechanically engaged with the cogwheel (42, 52, 62, 72) of another stepped gear of the stepped gear train or the gear of the output gear (7).

8. A gear reduction device, comprising a reduction gear (3) according to any one of claims 1 to 7 and a bracket (8) for supporting and centering a reduction gear shaft of at least one gear motor (1), wherein the reduction gear shaft is a shaft for centering at least one first motion transmission element (5) and a second motion transmission element (7), the first transmission element (5) and the second transmission element (7) being spaced apart from each other along the longitudinal direction (X3-X3) of the shaft and being rotatably movable relative to each other, the bracket (8) comprising at least one first plate (84) for supporting the second transmission element (7) and / or the first transmission element (5), the first plate (84) being configured to be passed through by the shaft and to be located between the first transmission element (5) and the second transmission element (7), wherein The reduction gear shaft is the central shaft (50), the first plate (84) is passed through by the central shaft (50), and the central shaft (50) is axially located between the first transmission element (5) and the second transmission element (7) relative to the central shaft (50).

9. The reduction gear according to the preceding claim, wherein: The bracket (8) includes a second plate (86) laterally spaced apart from the first plate (84), the second plate (86) being a support member for the third stage gear (6).

10. A gear motor (1), comprising a gear reduction device according to any one of claims 8 or 9, an electric motor (2) and a housing (10), wherein: The bracket (8) includes a base (80) supporting the first plate (84), and the base (80) abuts against the side wall of the housing (10). The support (8) comprises a foot (82) of the support resting on the bottom of the housing, the foot (82) carrying the first plate (84) relative to the housing (10).

11. Gear motor (1) according to the preceding claim, wherein The legs (82) of the bracket are each passed through by a connecting rod to connect the bracket to the housing. The bracket (8) preferably includes at least three legs (82), and / or the connecting rod is preferably a connecting screw.

12. The gear motor (1) according to any one of claims 10 or 11, wherein: The gear motor (1) comprises a cover (14), the central shaft (50) being rigidly connected to the cover (14), in particular by mechanical engagement with the cover (14), and / or Wherein the reduction gear (3) is according to claim 2, the shaft (60) for centering the third-stage gear (6) is rigidly connected to the bracket (8), in particular to the second plate (86).

13. The gear motor (1) according to any one of the preceding claims 10 to 12, wherein: The reduction gear (3) is a reduction gear according to any one of claims 4 and 5, and the shaft (40, 50, 60) of the stepping gear is parallel to the motor shaft (20) of the electric motor.

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